A mobile device may simultaneously connect to a cellular network and a wireless local network (WLAN) and exchange IP flows belonging to the same Public Data Networks (PDN) connection through different accesses. The operator may indicate how the IP flows may be routed through the available access systems, and may selectively offload some traffic to WLAN while using UTRAN or E-UTRAN for other traffic. This may be referred to as WLAN offload.
WLAN offload may be seamless or non-seamless. When WLAN offload is seamless, IP traffic flows belonging to the same or different applications may be moved seamlessly between a 3rd Generation Partnership Project (3GPP) access and WLAN. When WLAN offload is non-seamless, the local IP address changes each time the mobile device changes its location and connects to a different access point. The data session may need to be re-established, and the correspondent node may need to learn the new local IP address for the data exchange to resume.
Currently, certain services such as mobility services may require or prefer to use seamless WLAN offload. Mobility services may include, but not be limited to, voice over IP (VoIP), inter-technology handover (HO), IP flow mobility (IFOM), and/or bandwidth aggregation (BWA). Applications such as VoIP application and video streaming application may require mobility services. While it may be less costly and faster for the mobile device to use the local connection than using mobile network connections, mobility demanding applications may be forced to use mobile network connections even when the mobile device is substantially stationary.